The students who survived the South Korean Sewol ferry disaster are continuing their dramatic testimony against 15 crew members who fled as the vessel sunk.

On the second day of testimony at the trial in Ansan on Tuesday, the teenagers spoke of the heroic actions of their classmates, who handed out life vests as the ship went down.

Other students told of how they were pulled to safety by fellow passengers who lowered strips of curtain and fire hoses into the ferry, which was leaning heavily to one side.

All 75 children who survived the disaster are expected to give evidence at the trial, where the crew face charges ranging from murder to negligence for abandoning the ship.

On Monday, six teenage survivors, whose names were withheld to protect their privacy, described how they were given repeated orders not to move from their cabins.

The students from Danwon High School near Seoul revealed how chaotic the scene on the ferry was, saying they wore life jackets and were helped by friends to float out and leave flooded rooms. One of them said she saw some schoolmates swept away by the waters.

The six girls Monday were the first of 75 student survivors to give evidence in the trial at the Gwangju district court for two days, which has been moved to Ansan south of Seoul to accommodate the students.

Five of the students gave their evidence on Monday in the courtroom while one testified from another room via closed-circuit television.

Crew faces charges

The surviving crew members, including the captain, face charges ranging from homicide to negligence for abandoning the ship ahead of the passengers. Video footage of their escape triggered outrage across South Korea.

More than 300 people died after the ferry Sewol capsized on a routine trip on April 16, making it one of South Korea's worst civilian maritime disasters. Many of those killed were students from the same school on a class trip. Only 172 people, including the 75 students, were rescued and the rest are presumed to have drowned.

Passengers on board the ferry had been told to stay on board as it was sinking.

The trial comes after businessman Yoo Byung-un, who heads the family that owned the sunken ferry operator, was found dead in June.

Last week, the country's forensic agency said it was impossible to determine the cause of death as the body was badly decomposed.

Earlier on Tuesday, Yoo Byun-un's driver, Yang Hoe-jung, turned himself in, which could potentially unlock the mystery of the man's final days after the disaster.

Yang is thought by authorities to have been with Yoo, in the days before his body was found by a farmer at an orchard on June 12.